Fluorescent base analogues' usage in the characterization of nucleic acid molecules and their interactions

摘要

This invention provides methods, apparatus and kits for the quantitative and qualitative characterization of the nucleic acid molecule's behavior by modify the nucleic acid molecules to incorporate selected fluorescent base analogues (FBAs). The methods generally place one or more fluorescent base analogue into a nucleic acid molecule (e.g., an oligonucleotide) to replace the corresponding normal base(s), arrange fluorescent base analogues as intrinsic fluorescent probes by using direct excitation, indirect excitation, and excimer emission labeling schemes, introducing so modified nucleic acid molecules into the matrix with interested condition and measuring the fluorescent properties of the modified nucleic acid molecules at the specific emission wavelength of FBA(s). The apparatus is designed to irradiate the FBA(s) incorporated nucleic acid molecule at a wavelength in the range of 240 nm-280 nm and detect the fluorescent activities at the specific emission wavelength of the respective FBA(s). The kit provides oligonucleotides modified by multiple FBAs in the position of critical portions. It utilizes simultaneous indirect excitation labeling scheme for qualitative and quantitative investigation of nucleic acid molecules' interaction in vitro and in vivo.